The present invention relates generally to pumps. More particularly, the present invention relates to impellers and wear plates for use in a pump assembly.
This invention relates to the field of pumps, and more particularly, to industrial type pumps and related pump components. For many applications, the fluid being pumped may include suspended solids such as sand, silt, rocks, rags etc. Solids suspended in the fluid being pumped may sometimes cause the pump to become clogged. For example, rags and other fibrous or stringy materials suspended in the fluid may become wrapped around the impeller of the pump. This may reduce the efficiency of the pump.
Cavitation may also reduce the efficiency of a pump. Cavitation often occurs when there is a localized area of low pressure within the fluid in the pump. When the pressure at a particular point is reduced to the vapor pressure of the liquid being pumped, bubbles form. During cavitation, many bubbles may form and collapse. When a bubble collapses, a localized area of very high pressure is formed near the collapsed bubble. The very high intermittent pressures created during cavitation can cause damage to those portions of the pump that are near the cavitation. Cavitation also tends to reduce the overall efficiency of the pump, as energy is typically wasted when cavitation disrupts the smooth flow of fluid through the pump.
The present invention provides a pumping system for pumping water, sewage or other pumped material from one location to another. A pump impeller in accordance with one embodiment of the present invention includes a core member having a back face, a front face, and a central bore extending therebetween. A first blade and a second blade are fixed to the front face of the core member. The first blade and the second blade each having a top edge. The top edge of the first blade and the top edge of the second blade preferably define a curved surface.
Each blade has a trailing portion terminating at a trailing edge and a leading portion terminating at a leading edge. The leading portion of the first blade preferably radially overlaps the trailing portion of the second blade. Likewise, the leading portion of the second blade preferably radially overlaps the trailing portion of the first blade. A first channel is defined by the leading portion of the first blade, the trailing portion of the second blade, and the front face of the core member. A second channel defined by the leading portion of the second blade, the trailing portion of the first blade, and the front face of the core member.
The above described impeller is preferably used in conjunction with a pump assembly having a volute with a front side, a rear side, and a rounded discharge cavity. A back plate is attached to the rear side of the volute, and a mounting flange is attached to the front side of the volute. A front plate is attached to the mounting flange by a plurality of fasteners. A plurality of adjustment bolts are disposed between the front plate and the mounting flange. The position of the front plate may thus be adjusted by loosening the fasteners and rotating the adjustment bolts. Preferably, the front plate includes a front face defining a curved surface, such as a toroidal surface. The toroidal surface preferably matches the curved shaped surface defined by the top ends of the impeller blades. The impeller is positioned between the front plate and the back plate in the volute.